Receptacle with an externally threaded neck closed by a crown cork

ABSTRACT

A container with an externally threaded neck adapted to be closed by a twist-off crown. The height of the threads as measured from the upper surface of the neck is greater than onequarter of the external diameter of the neck at the threads. The neck is provided with a ring below the threads having a diameter exceeding the external diameter of the neck at the threads by at least 10 percent. Standard bottles have external diameters equal to 25 mm, rarely greater than 26 mm; for such bottles, the ring diameter exceeds the external diameter by at least 2.5 mm. The ring protects and guides the fingers of the user when unscrewing the crown.

United States Patent 1191 Leenaards 1451 Nov. 27, 1973 RECEPTACLE WITHAN EXTERNALLY THREADED NECK CLOSED BY A CROWN CORK [75] Inventor:Antoine Joseph Leenaards,

Lausanne, Switzerland [73] Assignee: Crown Cork Seal Company, Inc.,

Philadelphia, Pa.

22 Filed: Aug. 11, 1971 21 Appl. No.: 170,868

[52] US. Cl. 215/39, 215/43 R [51] Int. Cl B65d 41/1 0 [58] Field ofSearch 215/39, 43, 31, 46 R [56] References Cited UNITED STATES PATENTS9/1971 Frisch et al. 215/39 1/1971 Howard 215/31 3,648,874 3/1972 Moller215/39 3,503,534 3/1970 Moller et al. 3,559,833 2/1971 Alonso 215/39Primary Examiner-George T. Hall A container with an externally threadedneck adapted to be closed by a twist-ofi' crown. The height of thethreads as measured from the upper surface of the neck is greater thanone-quarter of the external diameter of the neck at the threads. Theneck is provided with a ring below the threads having a diameterexceeding the external diameter of the neck at the threads by at least10 percent. Standard bottles have external diameters equal to 25 mm,rarely greater than 26 mm; for such bottles, the ring diameter exceedsthe external diameter by at least 2.5 mm. The ring protects and guidesthe fingers of the user when unscrewing the crown.

15 Claims, 8 Drawing Figures PATENTEDnuvev ms sum 2 CF 2 RECEPTACLE WITHAN EXTERNALLY THREADED NECK CLOSED BY A CROWN CORK The present inventionrelates to a container with an extemally-threaded neck adapted to beclosed by a twist-off crown having a skirt crimped over the threads.

I ers have not provided ease of opening in combination with afluid-tight seal between the crown and the bottle neck.

The most common bottle of the prior art is shown in FIG]. The neck ofthe bottle comprises three threads 1 on the side of the neck having aneck diameter D and an upper sealing surface 2 with a connecting radius3 therebetween. A connecting radius 4 joins the upper surface 2 with thecylindrical internal surface having a diameter D Note that the threadsbegin at a distance h from the upper sealing surface 2 and end at adistance h The distance h is generally less than onequarter of the neckdiameter D,.

In order to close a neck of this kind, a crown can be crimped on to thethreads as shown in FIG. 2. However, the gripping of the crown by handis difficult since the points of the skirt teeth 5 project outwardly andmay cut the fingers of the user when the crown is gripped. In ordertosolve this problem, certain manufacturers have blunted the points of theteeth of the crown at the time of its manufacture. In this connection,the crown which is shown in FIG. 3 is provided with a cylindrical edge 6instead of the points of the teeth. This solution to the problempresents other problems in manufacturing (the conventional presses forpunching out the crown are no longer suitable). Furthermore, such acrown may be difficult to unscrew.

Oftentimes, at the time of crimping, the cylindrlcal edge 6 is bent backunder the beginning of the thread located at the distance h from theupper sealing surface 2. This distance h is calculated by the bottlemanufacturer so as to be less than or substantially equal to the heighth of the crown before sealing. During sealing, the crown is deformed bythe action of the crimping jaw and its total height becomes h which isgreater than h due to the bending back of the cylindrical edge 6 underthe bottom of the thread. This bending back causes considerabledifficulty to the user who wishes to unscrew the crown. The problem ofgripping and unscrewing the crown thus remains unsolved.

The sealing ring of the crown utilized in closing the bottle of FIG. 1,can itself present a problem in removing or unscrewing the crown. Theprior art sealing ring (cork or plastic) of some crowns have resulted inits compression on the upper surface 2, along the coupling radius 3, andalso on the cylindrical external surface having the diameter D This inturn results in considerable friction which can prevent unscrewing byhand. Because of the difficulty in unscrewing by hand, somemanufacturers have provided a kind of bottle opener in the bottom of thebottle (serving as housing for the crown) which makes it possible toopen a bottle by using another bottle. This merely avoids the unscrewingproblem and does not solve the problem.

Some efforts have been directed toward reducing the friction of thecrowns sealing ring so as to provide the consumer with a crown which canbe removed by hand. These efforts have involved the shape of the ring aswell as its composition. One prior art solution is an annular sealingring which is compressed on the connecting radius'4, that is to saytowards the interior of the neck. With this type of ring, the crown isunscrewed with relative ease, but three drawbacks remain l. The pointson the te'eth'of the crown still project and may injure or cut the user.

2'. The bottom of the skirt of the crown (see FIG. 4) is frequently bentback under the beginning of the thread located at a distance h from theupper sealing surface. This is again due to the calculation of thedistance h,, which is substantially equal .to the height h of the crownbefore sealing. The result is a locking effect on the crown which tendsto prevent unscrewing.

3. The sealing joint is compressed on a connecting radius with theinternal cylindrical surface on the neck. This part of the bottle isparticularly difficult for the bottle maker to manufacture. There aretherefore large tolerances on the diameter and defects, which makefluid-tight sealing doubtful. Even where the tolerances are maintained,the internal pressure existing inside the closed bottle (in the case ofgassy liquids) outwardly deforms the base of the crown, and thisdeformation increases towards the center of the crown. A sealing ringsuch as that which has just been considered will therefore becomedecompressed and the seal may be broken.

FIG. 5 shows a conventional, commercially available crown which isintended to close the neck of a bottle such as that shown in FIG. 1while eliminating the third drawback, decompression of the sealing ring.The crown comprises as a sealing means an annular ring 7 surrounding abase coating 8. The ring 7 is wholly located inside a cylindrical zonewhich has substantially as its diameter, the neck diameter D Thus thering 7 lies partly in the skirt-bottom connecting zone of the shell andpartly on the bottom of the shell. Actually, it is located at the outerlimit of the shell-bottom. During sealing, this ring will becomecompressed on the upper surface 2, in a zone close to the connectingradius 3, and over at least part of the connecting radius 3. This offerstwo advantages 2 l. The compression zone of the ring on the bottle(towards the exterior) is a zone easy for the bottle maker to produce,and it may therefore be expected that the sealing surface has beenparticularly well made and within the appropriate tolerances.

2. If the internal pressure which exists in the stoppered bottle (againin the case of gassy liquids) deforms the bottom of the crown, thedeformation diminishes towards the exterior of the crown and the jointis not substantially de-compressed.

Fluid-tightness is thus substantially assured while the problem offriction of the ring on the glass bottle and the resultant problem ofunscrewing are partly solved since the seal is only formed between aring which rubs against a small surface of the bottle. On the otherhand, all the difficulties of manipulation and gripping remain i.e., theprojection of sharp points on the crown presenting a hazard to the userand the folding back of the bottom of the skirt under the bottom of thethreads with the resulting locking effect.

It is therefore an object of this invention to provide a containerhaving a neck receiving a twist-off crown which prevents injury to auser removing the crown.

It is a further object of this invention to provide a container having aneck receiving a twist-off crown which prevents locking of the crown onthe neck. I

It is a still further object of this invention to provide a containerhaving a neck adapted to receive a conventional twist-off crown havingminimum frictional engagement with the neck and forming a fluid-tightseal even when the crown is outwardly deformed.

In accordance with these and other objects, a bottle is provided havinga threaded neck adapted to receive a twist-off crown and a ring locatedbeneath the threads on the neck. The diameter of the ring issufficiently large to guide the fingers of the user and preventinjurious contact with the crown points at the bottom of the crimpedcrown skirt. In this connection, the diameter of the ring may exceed thediameter of the threaded neck by percent. In particular for conventionalbottle neck diameters, which vary only very slightly from a value of 25mm, the diameter of the ring exceeds that of the neck by at least 2.5mm.

Such a ring thus enables the resolution of the problem of the grippingof the crown for removal by unscrewing by protecting and guiding theusers fingers.

Also in accordance with these and other objects of the invention, thethreads on the neck of the bottle have sufficient height to prevent thelocking of the crown on the neck when the bottom of the skirt is crimpedinwardly. In this connection, the overall height of the threads may begreater than one-quarter of the neck diameter.

The further features and advantages of the present invention willfurther be brought out inthe description which follows below whereinreference is made to the accompanying drawings in which FIG. 1 is anelevational view of the neck of a prior art bottle;

FIG. 2 shows the neck of FIG]. in combination with a conventionaltwist-off crown;

FIG. 3 is an elevational view of a conventional prior art crown;

FIG. 4 is a partially sectioned view of the crown of FIG. 3 in place onthe bottle neck of FIG. 1;

FIG. 5 is a sectional view of the prior art crown of FIG. 3;

FIG. 6 is an elevational view of a bottle neck embodying the invention;

FIG. 7 shows the neck of FIG. 6 in combination with a conventionaltwist-off crown and FIG. 8 shows the details of a bottle neck accordingto the invention on an enlarged scale.

In accordance with the embodiment shown in FIG. 6, the externallythreaded neck forming the subject of the present invention comprisesfour threads 9, an upper pling radius 11, and also by a portion of thecoupling radius. It may be advantageous to utilize a very small couplingradius (close to a right angle) which has the effect of betterlocalizing the sealing surface (solely on the upper surface 10), andthus of better controlling the unscrewing force if this should provenecessary.

In accordance with one important aspect of the invention, the threadsbegin at a distance h;, from the upper surface 10. This distance is infact calculated so as to be greater than the height h of the crown offact the diameter D shown in FIG. 7, which is a precise indication ofthe'degree of closure of the crown on the threads. This diameter D isgenerally determined by the crown manufacturer.

As mentioned above, the diameter D., of the ring 12 of the invention isequal to or greater than the crimping diameter D of the crown. Thisdiameter D, is a function of the diameter D, of the orifice (not shown)of FIG. 6 and generally, in the range of neck diameters approximatelyequal to 25 mm, we have The ring of the present invention thus has itsdiameter defined under these conditions by the relation In accordancewith another important aspect of the invention, the neck as shown inFIG. 6 is provided with a ring 12 having a diameter D.,. This ringprevents the user from hurting his fingers at the time of unscrewing thecapsule as shown in FIG. 7. Note that the points of the teeth 5 whileprojecting, cannot injuriously contact the users fingers 13, since theinward movement of the fingers is limited by the ring 12 having adiameter D., greater than the diameter of the crown D The usersprincipal contact is with the ring 12 having a smooth surface and notthe projecting points 5 of the crown.

In the crown industry, a closure is characterized by a magnitude knownas the crimping size. This is in FIG. 5 (or of FIG. 3) before closing soas to remain greater than the height h' which this crown may have aftercrimping. The conditions are therefore h h" h It is thus readilyunderstood that the base of the skirt of the crown can no longer be bentback under the beginning of the thread and the known locking effect isthereby eliminated.

It has previously been seen that the distance h, utilized on the neck ofFIG. 1 was in general less than one-quarter of D 6.25 mm for neckdiameters close to 25 mm. In the case of the embodiment of the presentinvention, the distance h thus becomes greater than one-quarter of thediameter D, in the aforesaid range.

The position of the ring with respect to the bottom of the crown mustenable the users fingers to be guided without interfering with thecrown. It has been found that the distance from the upper sealingsurface to the top of the ring must not exceed one-quarter of the neckdiameter by more than approximately 50 percent. Tests have shown thatwhen this limit is exceeded, the beneficial result sought after is nolonger present. The position of the ring will be further describedrelative to FIG. 8

The neck diameter D, of the cylindrical surface 17 is the externaldiameter at the free end of the neck. The cylindrical surface 17 extendsaxially to the position A at which the threads begin. At this point andextending in the opposite direction begins a zone of widening 14, whichconnects the cylindrical surface to the ring.

The term top of the ring refers to the axial position E, where thediameter of the neck has a certain minimum value D Below this point thering has a cylindrical or slightly truncated conical surface terminatingin a narrowing zone 16. The diameter of the neck is there fore a limitedaxial distance equal to that of said neck diameter.

The term bottom of the ring refers to the axial position F where thediameter becomes less than the said value D According to thisdefinition, the width of the ring ought not to be more than 50 percentgreater than onequarter of the diameter D Further, the distance H fromthe upper s'ealing surface to the bottom of the ring will beadvantageously limited to value less than twice the height h of thethreaded portion such that the width (h h,,) of the ring will remain ingeneral less than half the height h;,.

As has already been described, fluid-tightness is assured by the annularring of FIG. 5. A ring of this kind is compressed against the uppersealing surface of the neck and to some extent against the connectingradius 1 l. The choice of the nature and the weight of the sealingmaterial which constitutes this ring makes it possible to determine theunscrewing force required with an accuracy which will increase as theconnectingradius 11 is decreased. Experience has shown that theconnecting radius ought not to be greater than one millimeter in orderthat the objects according to the invention be satisfied.

The foregoing considerations apply to common bottles the necks of whichhave, as noted above, free end diameters close to mm, the differencefrom this value rarely exceeding 1 mm. However, it now appears thatthere is a certain tendancy towards neck diameters of mm or more.Research has shown that the dimensions set forth according to theinvention for a range of neck diameters which differ only very slightlyfrom 25 mm remain valid for the now proposed neck diameters.

According to a further aspect of the invention, the

limits hereabove defined for the usual 25 mm range will beadvantageously also adopted in case of neck diameters which aresubstantially outside said range. This will be the case as well for theheight of the threads measured from the upper sealing surface of theneck as for the guiding radial protusion formed by the ring and for theaxial position of said ring. One is thus led to adopt for the diameter1)., of the ring a minimum value which exceeds the neck diameter U by atleast one-tenth of the 25 mm, that is 2.5 mm. In other words, thisarrangement assures a guiding ring surface 15 which protrudes over thecylindrical surface 17 of the bottle neck for at least 1.25 mm.

The height h of the threaded portion of the bottle neck will be in anycase greater than one-quarter of 25 mm, that is 6.25 mm.

The distance h, from the upper sealing surface to the top of the ring,which of course forms an upper limit for h ought not to exceed by morethan 50 percent the aforesaid limit of 6.25 mm.

Finally, the distance k from the upper sealing surface to the bottom ofthe ring should advantageously be held to values less than twice thedistance h such that the width (k h.,) of thering will remain as a ruleless than half of the distance h A perfectly satisfactory guiding effectis thus obtained with a ring width in the order of 3 mm.

in the appending claims the free end diameter D of the neck isdesignated by neck diameter.

What is claimed is:

l. A bottle adapted to be closed by a twist-off crown and comprising anexternally threaded neck having a plurality'of threads and a radiallyoutwardly-extending ring located beneath said threads, said ring havinga diameter at least equal to maximum diameter of a crown crimped on tosaid neck so as to prevent injurious contact between the fingers of auser and the edge of the crown skirt.

2. The bottle of claim 1 wherein said neck includes an upper sealingsurface adapted to be engaged by a crown, the height of said threadsmeasured to the top of said neck being at least equal to the height of acrown crimped on to said neck.

3. The bottle of claim 2 in combination with a twistoff crown having amaximum diameter not greater than said ring and a height after crimpingon to said neck not greater than said height of said threads.

4. The bottle of claim 3 wherein said neck includes an upper sealingsurface at said top thereof, a side surface carrying said threads, and aconnecting radius therebetween, said crown having a sealing ringcompressed substantially only against said upper sealing surface andsaid connecting radius.

5. The container of claim 1 wherein said neck includes an upper sealingsurface and the height of said threads as measured from said uppersealing surface of the neck is greater than one-quarter of the neckdiameter.

6. The container of claim 1 wherein said neck includes an upper sealingsurface and the distance from said upper sealing surface to the top ofthe ring is not greater than 1 1% times the height of said threads.

'7. The container of claim 1 wherein said neck includes an upper sealingsurface, a side surface carrying said threads, and a connecting radiustherebetween, said connecting radius being not greater than onemillimeter.

8. The container of claim 7 incombination with a twist-off crown.

9. The combination of claim 5 wherein said crown comprises a sealingring located substantially inside a cylindrical zone of said crownhaving a diameter substantially equal to the external diameter of saidside surface and adapted to be compressed substantially only againstsaid upper sealing surface and said connecting radius.

re. The container of claim 1 wherein said threads consist of four.

11. The container of claim 1 wherein said neck includes an upper sealingsurface and the height of said threads as measured from said uppersealing surface is greater than 6.25 mm.

12. The container of claim 111 wherein the distance from upper sealingsurface to the top of the ring is not greater than 1 1% times 6.25 mm.

13. The container of claim 11 wherein the distance from said uppersealing surface to the bottom of the ring is not greater than twice saidheight of the threads.

14. The container of claim it wherein the width of the ring is less thanhalf the height of said threads.

15. The container of claim 11 in combination with a

1. A bottle adapted to be closed by a twist-off crown and comprising an externally threaded neck having a plurality of threads and a radially outwardly-extending ring located beneath said threads, said ring having a diameter at least equal to maximum diameter of a crown crimped on to said neck so as to prevent injurious contact between the fingers of a user and the edge of the crown skirt.
 2. The bottle of claim 1 wherein said neck includes an upper sealing surface adapted to be engaged by a crown, the height of said threads measured to the top of said neck being at least equal to the height of a crown crimped on to said neck.
 3. The bottle of claim 2 in combination with a twist-off crown having a maximum diameter not greater than Said ring and a height after crimping on to said neck not greater than said height of said threads.
 4. The bottle of claim 3 wherein said neck includes an upper sealing surface at said top thereof, a side surface carrying said threads, and a connecting radius therebetween, said crown having a sealing ring compressed substantially only against said upper sealing surface and said connecting radius.
 5. The container of claim 1 wherein said neck includes an upper sealing surface and the height of said threads as measured from said upper sealing surface of the neck is greater than one-quarter of the neck diameter.
 6. The container of claim 1 wherein said neck includes an upper sealing surface and the distance from said upper sealing surface to the top of the ring is not greater than 1 1/2 times the height of said threads.
 7. The container of claim 1 wherein said neck includes an upper sealing surface, a side surface carrying said threads, and a connecting radius therebetween, said connecting radius being not greater than one millimeter.
 8. The container of claim 7 in combination with a twist-off crown.
 9. The combination of claim 8 wherein said crown comprises a sealing ring located substantially inside a cylindrical zone of said crown having a diameter substantially equal to the external diameter of said side surface and adapted to be compressed substantially only against said upper sealing surface and said connecting radius.
 10. The container of claim 1 wherein said threads consist of four.
 11. The container of claim 1 wherein said neck includes an upper sealing surface and the height of said threads as measured from said upper sealing surface is greater than 6.25 mm.
 12. The container of claim 11 wherein the distance from upper sealing surface to the top of the ring is not greater than 1 1/2 times 6.25 mm.
 13. The container of claim 11 wherein the distance from said upper sealing surface to the bottom of the ring is not greater than twice said height of the threads.
 14. The container of claim 11 wherein the width of the ring is less than half the height of said threads.
 15. The container of claim 11 in combination with a twist-off crown. 